1. Field
Aspects of embodiments of the present invention relate to a secondary battery, and more particularly to a secondary battery including a cap assembly in which bending is prevented or reduced.
2. Description of the Related Art
Common polygonal secondary batteries include an electrode assembly, a can accommodating the electrode assembly, and a cap assembly combined with the can. The top of the can is open and the cap assembly is combined by sealing the opening of the can. In this configuration, the size of the cap assembly is set larger than the opening of the can and the cap assembly is press-fitted in the can.
However, when the cap assembly is inserted in the can, as described above, a portion of the long sides of the cap assembly is bent in the can. Accordingly, it is difficult to pack the outer side of a bare cell, because the outer side of the bare cell is bent by the above structure.